黄土区沟道泥沙真菌群落结构功能变化特征  

Variations of Sediment Fungal Community Structure and Function Across a Catchment in Loess Plateau

作　　者：贺高航 李彤彤 王晓璐 张宁 陈岩 高胜 王蕊[1,2,3] 郭胜利 HE Gaohang;LI Tongtong;WANG Xiaolu;ZHANG Ning;CHEN Yan;GAO Sheng;WANG Rui;GUO Shengli(Institute of Soil and Water Conservation,Northwest A&F University,Yangling 712100,China;College of Natural Resources and Environment,Northwest A&F University,Yangling 712100,China;Institute of Soil and Water Conservation,Chinese Academy of Sciences and Ministry of Water Resources,Yangling 712100,China)

机构地区：[1]西北农林科技大学水土保持研究所,陕西杨凌712100 [2]西北农林科技大学资源环境学院,陕西杨凌712100 [3]中国科学院水利部水土保持研究所,陕西杨凌712100

出　　处：《水土保持研究》2023年第5期274-282,共9页Research of Soil and Water Conservation

基　　金：国家自然科学基金(42107360);中央高校基本科研业务费(2452021032)。

摘　　要：[目的]探究沟道泥沙迁移过程中的真菌群落结构功能变化特征,有利于完善泥沙侵蚀研究,可为侵蚀区生态系统演变过程提供理论支撑。[方法]基于黄土区典型小流域汛期主沟道不同空间位置的悬移质泥沙,通过ITS高通量测序,分析真菌群落从沟头到把口的变化特征及其影响因素。[结果]从沟头到把口,悬移质泥沙真菌群落shannon指数和chao1指数降低23.2%和33.2%,真菌群落多样性和丰富度沿泥沙迁移方向显著下降(p<0.05),且真菌群落结构存在空间异质性。从沟头到把口,子囊菌门(Ascomycota)和担子菌门(Basidiomycota)相对丰度降低7.6%和6.9%;腐生营养型真菌(Saprotroph)相对丰度降低6.0%。真菌共发生网络从沟头到把口趋于简化,群落稳定性和抗干扰能力逐渐减弱。悬移质泥沙真菌群落多样性(shannon)和丰富度(chao1)与有机碳(OC)、全氮(TN)、速效磷(Olsen-P)含量呈显著负相关关系(p<0.05),与>63μm粒级含量呈显著正相关关系(p<0.05)。[结论]沟道泥沙真菌群落的多样性、丰富度和稳定性在迁移过程发生变化,粒级组成和碳氮磷含量是其重要影响因素。[Objective]Exploring variations of fungal community structure and function during sediment transfer across a catchment is conducive to consummating the study of sediment erosion,and provides theoretical support for understanding the evolution process of the ecosystem in eroded region.[Methods]Suspended sediments were collected from different geospatial locations under the main valley bottom during flood season at a typical small watershed in Loess Plateau.Physicochemical properties of suspended sediments were measured and the characteristics of sediments fungal community were determined by the high-throughput sequencing of ITS.[Results]Shannon index and chao1 index of suspended sediments fungal community decreased by 23.2%and 33.2%from gully head to dam,which meant fungal community diversity and richness were decreased significantly along the direction of sediment transfer(p<0.05),and the spatial heterogeneity showed in fungal community structure.From gully head to dam,the relative abundance of Ascomycota and Basidiomycota decreased by 7.6%and 6.9%,and the relative abundance of Saprotroph decreased by 6.0%.The fungal co-occurrence networks became simpler from gully head to dam,which meant the stability and anti-interference ability of fungal community were weakened gradually.The fungal community diversity(Shannon)and richness(chao1)of suspended sediments were negatively correlated with OC,TN and Olsen-P(p<0.05),were positively correlated with the>63μm content(p<0.05).[Conclusion]The diversity,richness,and stability of sediment fungal community changed during transport process across a catchment,particle composition and CNP contents appeared to be the crucial influence factors.

关 键 词：悬移质泥沙 真菌群落 粒级组成 养分含量 

分 类 号：X172[环境科学与工程—环境科学]